Di(n-butyl) Phthalate가 태자와 신생자 SD Rat의 면역계 발생에 미치는 영향

정승태(Seung-Tae Chung),엄준호(Juno Ho Eom),박재현(Jae Hyun Park),정형진(Hyung-Jin Chung),황인창(In-Chang Hwang),김동섭(Dong Sup Kim),하광원(Kwang Won Ha),김형수(Hyung Soo Kim) 한국독성학회 2001 Toxicological Research Vol.17 No.2

Some of endocrine disruptors with sexual hormone-like effects have been increasingly reported to be immunotoxic in many species in recent several years. Phthalate esters have possible effects on the endocrine system. Prenatal exposure to di(n-butyl) phthalate (DBP) has been reported to impair the androgen-dependent development of the male reproductive tract in rat. Therefore, the immunomodulatory effect of DBP was investigated in the developing immune system of fetal and neonatal Sprague-Dawley rats. Timed-bred pregnant SD rats were given to the doses of 0, 250, 500, and 750 mg DBP/kgㆍbody weight/day by gavage once a day from gestational day (GD) 5 to 18. On GD19 or GD22/postnatal day one (PD1), the dams were euthanized, and the changes in organ weights and thymus phenotypes were examined their offsprings. At 750 mg DBP/kg ㆍb.w./day in maternal exposure group, GD19 fetuses showed decreases in body weight. The spleen/body weight ratios were reduced in GD19 fetuses from the dams exposed to 500 and 750 mg DBP/kgㆍb.w./day. There were no significant changes in thymus and spleen cellularities though these cellularities showed a tendency to decrease in a dose dependent way. In the DBPGD22/PDl offsprings, the body weights, the relative organ weights and the cellularities did not exhibit alteration. Additionally, the percentages of CD3+(CD4+CD8+, CD4+CD8-, CD4-CD8+, and CD4-CD8) and CD3-(CD4+CD8+, CD4+CD8-, CD4-CD8+, and CD4-CD8) thymocyte subsets were not changed in any DBP-treated group. The proliferative responses oj splenic T cells to Con A and B cells to LPS were decreased in all DBP-exposed GD22/PDl offsprings.

돼지고기 중 알레르기 유발성분의 동정

정혜주(Hye Joo Chung),박재현(Jae Hyun Park),김재희(Jae Hee Kim),김영옥(Young Ok Kim),정승태(Seung Tae Chung),김진호(Jin Ho K im),조은득(Eun Deuk Cho),조대현(Dae Hyun Cho),노건응(Geun Woong Noh),김동섭(Dong Sup Kim) 대한약학회 2001 약학회지 Vol.45 No.1

The pork meat been reported as one of the food occurring allergic reactions predominantly to korean. To identify the potential food allergens in pork meat, sera were collected from 25 allergic patients to the pork meat and 10 allergic patients not to pork meat as well as 5 normal subjects after skin prick test and open food challenge test. Crude extracts were prepared by blending raw pork meat in phosphate buffered saline (pH 7.0) and the heat treatment on crude extracts was carried to characterize sensibility of the allergens to heat. ELISA was performed to determine specfic IgE antibody levels of allergic patients to pork meat, and resulted in twofold higher mean value than that of tolerated patients. Extracted proteins from pork meat was separated with SDS-PAGE followed by immunoblotting using sera from pork sensitive patients and control subjects, respectively. The IgE binding response to pork meat by immunobots correlated with quentitative specfic IgE value of each person. Immunoblots showed four prominent IgE-binding bands (66, 60, 50, 44kDa) in crude extract, but two bands of those (60, 44kDa) were heat-labile. These results suggest that most prominent allergens from pork meat are four components(66, 60, 50, 44 kDa) in korean and the heat treatment on allergen is additional parameter to characterize allergen.

Curcumin애 의해 유도된 egr-1 및 c-myc 유전자에 의한 발현 감소가 CpG oligodeoxynucleotide로 촉진된 미성숙 B 림프종 BKS-2의 성장 증가 억제

한성수(Seong-Su Han),정승태(Seung-Tae Chung) 한국독성학회 1999 Toxicological Research Vol.15 No.3

To investigate the role of egr-1 and c-myc in immature murine B cell lymphoma BKS-2, we treated BKS-2 with curcumin and(or) CpG oligodeoxynucleotide(ODN). CpG ODN increased proliferation of BKS-2 cells up to 170% at 10 μM. The mRNA levels of egr-1 and c-myc were dramatically upregulated as early as 30 min following stimulation and decreased eventually with the 1 μM of CpG ODN. c-myc mRNA level was increased and peaked at 3 h. Curcumin treatment caused growth arrest of BKS-2 by dose-dependent manner and dramatically downregulated the expression of egr-1 and c-myc after 0.5 h until 6 h. Moreover, BKS-2 cells were growth arrested from CpG ODN mediated proliferation by the treatment with curcumin. 50 μM of curcumin treatment suppressed the expression of egr-1 and c-myc upregulated by CpG ODN. In summary. Curcumin caused the growth arrest of BKS-2 immature B-cell lymphoma and also inhibited the proliferation effect of CpG ODN to BKS-2 via downregulation of egr-1 and c-myc.

새로운 간염치료제인 수용성 DDB 유도체 (DDB-S)의 항원성 평가

한형미,김진호,최경백,김형수,정승태,문전옥,이치호,김주일,Han, Hyung-Mee,Kim, Jin-Ho,Choi, Kyoung-Baek,Kim, Hyung-Soo,Chung, Seung-Tae,Moon, Jeon-Ok,Lee, Chi-Ho,Kim, Joo-Il 한국독성학회 1998 Toxicological Research Vol.14 No.3

Dimethyl dimethoxy biphenylate (DDB) is an agent used to treat hepatits. DDB-S (DDB-soluble), a new DDB derivative, was synthsized to increase water solubility of the original DDB. In the present study, the antigenic potential of DDB-S was examined by active systemic anaphylaxis (ASA), passive cutaneous anaphylaxis (PCA) and passive hemagglutination (PHA) tests. The experimental groups consist of a low dosage group, a high dosage group, he group emulsified with Freund's complete adjuvant (FCA, ASA test) or an alum (PCA and PHA tests) and the macromolecule conjugate group emulsified with FCA or an alum. In the ASA test, all experimental groups showed negative responses whereas the positive control group given ovalbumin plus FCA showed severe anaphylactic responses. In the heterologous PCA test using mice and rats, positive responses were not detected in any of the experimental groups. In the PHA test, all experimental groups showed negative responses whereas the positive control group given ovalbumin plus an alum showed 512~2048 PHA titers. These results demonstrated that DDB-S does not have any antigenic potential. These can be utilized as a part of preclinical data for the development of DDB-S as an intravenous injection.

유전자변형 롱과 지연 콩의 알레르기 유발원 비교

박재현(Jae Hyun Park),정승태(Seung Tae Chung),김재희(Jae Hee Kim),김지영(Ji Young Kim),노건웅(Geum Woong Noh),김동섭(Dong Sup Kim),김형수(Hyung Soo Kim) 대한약학회 2001 약학회지 Vol.45 No.3

Genetically modified organism (GMO) using reoombinant DNA technique has been expo- nentially increased, however there are still arguments for the safety of GM foods. The objective of this researoh was to compare the allergens of GM soybean(Roundup ReadyTM) with conventional soybeans. Each soybean eBrhacts were prepared as crude extracts, heated extracts, and as heated and simulated gastric fluid (SGF)- digested samples to characterize the stability of allergens to physicoohemical treatment. Positive sern from 20 soybean-sensitive patients and control sera from 5 normal subjects were used to identify the endogenous allergens in soybeans. Specific-IgE binding activities To each soybean preparations were evaluated by ELISA and immunoblot technique. In ELISA result, IgE-binding activities of positive sera to soy crude extracts generally showed two fold higher mean value than those of control sera however there was no significant difference between GM soybean and natural soybean varieties. Extracted proteins form each of the soybean preparations were separated with SDS-PAGE. The band pattern of GM soybean was very similar to those of natural soybean varieties. Immunoblots for the different soybeans revealed no differences in IgE-binding protein patterns, moreover, disclosed five prominent IgE-binding bands (75,70,50,44 and 34 kDa) in crude extracts, four (75,70,44 and 34 kDa) in heated preparations, one (50kDa) in heated and SGF-digested preparations. These IgE binding bands were consistent is previously reported results on the soybean. These results indicate that GM soybean (Roundup ReadyTM) is no different from natural soybean in terms of its allergen.

Balb/c 마우스에서 유기인계 농약인 Pirimiphos-methyl 및 Methidathion의 면역독성

엄준호(Juno H. Eom),정승태(Seung-Tae Chung),박재현(Jae Hyun Park),길정현(Jung Hyun Kil),이종권(Jong Kwon Lee),오혜영(Hye Young Oh),김형수(Hyung Soo Kim) 한국독성학회 2004 Toxicological Research Vol.20 No.4

Primiphos-methyl and methidathion as organophosphorus (OP) pesticides were tested for their immunotoxic effects on Balb/c mice. Three dose levels of primiphos-methyl (10, 60, or 120 mg/kg/day) and methidathion (0.5, 2.5 or 5.0 mg/kg/day) were administered orally in the mice for 4 weeks. After, changes in body weight gain, relative weight of spleen and thymus, viable splenic cell numbers, surface marker on immune cell, and proliferation activity were investigated. Results showed that neither Pirimiphos-methyl nor methidathion dosages changed significantly body weight, relative thymus and spleen weight, and thymus and spleen cellularities of the mice, but high dose treatment (120 mg/kg) of pirimiphos-methyl significantly decreased relative spleen weight and spleen cellularity of the mice. No alterations were observed in changes of LPS-proliferation response of splenocytes by exposure to any dose of pirimiphos-methyl and methidathion. However, pirimiphos-methyl dosages reduced ConA-proliferation response of splenocytes and both methidathion and pirimiphos-methyl decreased the ability of antibody production to SRBC. The results indicate that 28 days exposure to the high dose of pirimiphos-methyl suppress the function of splenic T and B cell function, and methidathion reduce the immune responsibility of B cell in mice without the changes in lymphoid organ weight or viability of splenocytes. Pirimiphos-methyl is more immunotoxic than methidathion although this has higher general toxicity than that.

릴레이를 이용한 차량용 배터리의 가변 충전기

송성근(Sung-Geun Song),정승태(Seung-Tae Chung),강성구(Sung-Gu Kang),이상훈(Sang-Hun Lee) 한국조명·전기설비학회 2012 조명·전기설비학회논문지 Vol.26 No.9

This research is to develop satiable battery charger with a variety of capacity and voltage specifications of battery. For this, voltage or current were controlled through buck converter which is DC voltage that already received three-phase at primary side and passed bridge rectifier diode. And, it was comprised of full-bridge converter and HFTR for insulation and a square wave AC. The transformer primary side was comprised in series to divide certain charging current and the secondly side was comprised of 6 fixed transformers so that they can generate certain amount of power and various output voltage through relay parallel compound 6 DC Link outputs. To confirm such structures verification and validity, simulation with PSIM was conducted, and validity of proposed variable charger system was verified through 3kW stack production.

Agrobacterium tumefaciens A348 에서 virE 프로모터의 활성

엄진성(Jin Seong Eum),정승태(Seung Tae Chung),안정선(Chung Sun An),심웅섭(Woong Seop Sim) 한국식물학회 1991 Journal of Plant Biology Vol.34 No.4

To elucidate the regulatory mechanism of virE operon from vir regions (virA, virB, virC, virD, virG, virE) of pTiA6 which have been known to be essential for efficient crown gall tumorigenesis in plants, the activity of the truncated virE promoter was analyzed. pSM358cd, a recombinant plasmid in which virE :: Tn3-HoHo1 (Tn3-promoterless lacZ) was cloned into SalⅠ site of pVK102, was digested with SalⅠ and virE :: Tn3-HoHo1 was seperated from pVK102. To construct the truncted virE recombinant plasmids (pJS031, pJS051, pJS102, pJS201, pJS301), 5`-end of virE promoter was deleted with BAL31 and cloned into pVK102 and then transferred into A. tumefaciens A348 (pTiA6). According to the activity of the truncated virE promoter in recombinant plasmids, they were classified into two groups, pJS031, pJS051, pJS101 and pJS201 belong to a functional group and pJS301 is a non-functional. The size of deleted nucleotides of pJS201 and pJS301 seemed to be about 130 nucleotides and about 250 nucleotides from 5`-end of virE promoter, respectively. Hence it was thought that the essential site of the virE promoter was located between about 130th nucleotide and 250th nucleotide from 5`-end of the virE promoter.

광독성시험의 동물대체법에 관한 총설

김영옥(Young-Ok Kim),정혜주(HyeJoo Chung),정승태(Seung-Tae Chung),조대현(Dae-Hyun Cho) 한국독성학회 1999 Toxicological Research Vol.15 No.3

It is essential to determine the potential photo-sensitizing properties of chemicals before marketing, as unwanted cutaneous photosensitivity can be induced by any of several hundred chemicals. Until now, the animal studies using guinea pigs, rabbits, rats or mice have been employed for investigating the photo toxic effects of chemicals on the skin. However, it is needed to develop the alternative methods to animal tests, because the animal test costs a great deal, takes long time and requires specialized facilities. In addition, EU proposed the prohibition of animal testing on cosmetics from 2000. In the recent GECD draft proposal for a new guideline on acute dermal photoirritation testing, in vitro screening tests includes in a sequential test strategy. According to the proposal, it should have priority over any animal tests. During the EC/CGLIPA validation study many in vitro photo toxicity test systems, covering several mechanisms of phototoxicity, have been developed. Consequently, it is predicted that in vitro photo toxicity tests will substitute for in vivo tests. At this point, it is necessary for us to review the mechanisms of phototoxicity, standard protocols of in vivo tests, in vitro tests not only for screening purposes but for mechanistic studies, and phototoxicity guideline of GECD, Korea and Japan.

일정광량 방식의 광자주사현미경 제작

김지택,최완해,조재홍,장수,김달현,구자용,정승태,Kim, Ji-Taek,Choi, Wan-Hae,Jo, Jae-Heung,Chang, Soo,Kim, Dal-Hyun,Koo, Ja-Yong,Chung, Seung-Tae 한국광학회 1999 한국광학회지 Vol.10 No.3

가열인장(heating and pulling)방법을 이용하여 개구부 직경이 약 100nm 이하인 광섬유 탐침을 제작하였으며, 이를 이용하여 일정광량 방식의 광자주사현미경을 제작하였다. 광섬유 탐침을 물체에 미세하게 접근시켜서 물체면을 주사하기 위하여 원통형 PZT(piezoelectric transducer)를 x-y-z의 3부분으로 나누어 z축의 미세접근 및 1.43$\mu\textrm{m}$ $\times$ 1.76$\mu\textrm{m}$의 면적을 x-y축으로 주사할 수 있는 3차원 PZT 주사기를 제작하였다. 그리고 광섬유 탐침에서 검출되는 에바네슨트라의 광량이 항상 일정하도록 전자적인 되먹임 회로에 의한 광섬유 탐침이 1$\lambda$ ($\lambda$ 는 입사파장임) 이하의 근접장 영역에서 물체로부터의 높이가 일정하도록 하였다. 그리고 이렇게 제작된 일정광량 모드의 광자주사 현미경을 이용하여 정상파 형태의 에바네슨트파를 측정하였다. We made sharp optical fiber tips with less than 100 nm diameter by using the heating and pulling method with a good repetition and fabricated the photon scanning tunneling microscope (PSTM) using constant intensity mode. The 3-dimensional PZT (Piezoelctric transducer) scanner made of a long PZT tube is consisted of three divided parts, that is, a pair of $\pm$ x and a pair of $\pm$y scanning parts and a z scanning part for the fine approach and scanning. The scanning dimension is 1.43 $\mu\textrm{m}$$\times$1.76 $\mu\textrm{m}$. The height of a optical tip to maintain a constant height within $1/{\lambda}_0$ (${\lambda}_0$ is the incident wavelength) from surface of a specimen to a optical tip is controlled automatically by using the electric feedback circuit. The 3-dimensional shape of standing evanescent waves generated on the surface of a dove prism was measured successfully by using the constant intensity mode PSTM.